Insects are called bugs because a long, long time ago, people started using the word "bug" to describe all sorts of tiny crawling or flying creatures they saw around them.

The word "bug" actually originally meant any small insect-like creature. As time passed, people started to use the word more specifically to talk about a certain group of insects with certain features, like beetles, ants, and butterflies.

Nowadays, we still call insects "bugs" because it's a word that has been used for a very long time to talk about these little creatures. It's like a special nickname we use to group all these tiny animals together.

So, insects are called bugs because a long time ago, people started using the word to talk about small crawling or flying creatures, and it stuck around until today!